IP-
TCP/IP, - Internet Protocol (IP), - (OSI). 4- (IP v.4, RFC 791, 1981). 5 ST2, . 1998 6- IP- (RFC 2460, 1998). , - 2012 IP v.6 8% ( ), - 4%, - 3.5%. - 2015 IPv6 IP- 9%. IP v6 , , , .
IP- ( ). , , TCP. IP :
, ( ) ;
.
IP-
IP- , . 6.3.
( 20 ) : , 40 , (Padding), , , 32 . .
(Version) . , , . 6 4. , , .
(Internet Header Length, IHL) - 32- . 20 (5 ). ( 32- ) 5.
(Type of service, ToS). IP- . (0-7); 3-5 : ( , /), ( , /) ( , /). , ; , . , IP- . . , 6 (Differentiated Services Code Point, DSCP; RFC 2474, 2475). , , 64 . , . , 12 . , 3 DSCP , , . 6 7 DSCP . (ECN, Explicit Congestion Notification). 6 , ECN ( ECN). 7 (-, Congestion Experienced) , .
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(Total length) - , 65535 . , , , . , Ethernet 1518 , FDDI 4096 .. (Maximim Transmission Unit, MTU) , , . MTU , , IP . RFC 791 , IP- , 576 ( ). , , MTU, . .
, . ( ) - ( ); , . Dont Fragment - , More Fragment ; 0. , ( IP ) 8 . 8- ; , .
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(Time to live, TTL) - , . , . . . 255. TTL -.
(Protocol) (TCP, UDP, ICMP, OSPF, ) IP-. . .
6.1
Reserved | ||
ICMP | Internet Control Message Protocol | |
IP | Internet Protocol | |
TCP | Transmission Control Protocol | |
UDP | User Datagram Protocol | |
OSPF | Open Shortest Path First |
(Header checksum) , . ( TTL, ), . , IP.
(Source IP address) (Destination IP address) (32 ), . IP- .
(Options) , . RFC 791 8 . , , (), . . , , IP-, . , . IP- .
IP
IP- . , , . , (, ..) , . IP RFC 990 RFC 997.
:
1. , . Ethernet Token Ring 6- MAC- , -.
2. (IP-), 4 .
3. , IP-.
IP- , .. . 2 , , . , , . , 32 . . 6.4.
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IP- 4- , . . , , 10000000 10000111 01000100 00000101 128.135.68.5. 10, , B, , , 16 , 16 .
. , 127... ( , 0) , . , TCP/IP . , 127, . , , , 1 . 255.255.255.255 , -, . , , , , . 1. , , 184.90.255.255 , 184.90.0.0.
. 6.4. , . , 26+25+ .+20 1 =126 ( , ). 224-2 = 16 777 214 . , 50% . 6.2. B C.
6.2.
IP- (%) | ||||
001 126 | 16 777 214 | |||
128 191 | 16 384 | 65 534 | ||
192 - 223 | 2 097 152 | 12,5 |
, , - Internet Assigned Numbers Authority (IANA). IANA IP- (LIR), . , , - .
IP-
, . 1985 (RFC 950). . , 65000 . , . , . . , . , , . 80- . , ( ) () , , .
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; , , . , , (. 6.5).
. , 6 62 , 1022 . , , .
. , , , , . . 32- , , , 1, , 0. , , 132.10.0.0 , 100 . 7 (27 =128), . 9 , 16, B , ( 29-2=510). 16 , , . , 132.10.12.128, :
132.10.12.129, 132.10.12.130,.,132.10.12.254
11111111 11111111 11111111 10000000 (255.255.255.128).
132.10.12.176,
10000100 00001010 00001100 10110000,
(255.255.255.128), . :
10000100 00001010 00001100 10000000,
132.10.12.128. , , .
, IP- (- , , ). () , . , .
, , , . 132.10.12.176/25. 6.3. . , , , , . , . 6.3., 193.10.1.0 193.10.1.0/25, 193.10.1.0. , 193.10.1.255 193.10.1.224/27.
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6.3.
193.10.1.0 | 255.255.255.0 | 193.10.1.0/24 | ||
1 | 193.10.1.0 | 255.255.255. 192 | 193.10.1.0/26 | |
2 | 193.10.1.64 | 255.255.255. 192 | 193.10.1.64/26 | |
3 | 193.10.1.128 | 255.255.255. 192 | 193.10.1.128/26 | |
4 | 193.10.1.192 | 255.255.255. 192 | 193.10.1.192/26 |
(RFC 950) , "" ( ). . , . (Variable Length Subnet Mask, VLSM) . 2n (). , . 6.4 , VLSM.
6.4
"" | ||||
2 147 483 648 | 2 147 483 646 | 128.0.0.0 | 128 A | |
1 073 741 824 | 1 073 741 822 | 192.0.0.0 | 64 A | |
536 870 912 | 536 870 910 | 224.0.0.0 | 32 A | |
268 435 456 | 268 435 454 | 240.0.0.0 | 16 A | |
134 217 728 | 134 217 726 | 248.0.0.0 | 8 A | |
67 108 864 | 67 108 862 | 252.0.0.0 | 4 A | |
33 554 432 | 33 554 430 | 254.0.0.0 | 2 A | |
16 777 216 | 16 777 214 | 255.0.0.0 | 1 A (256 B) | |
8 388 608 | 8 388 606 | 255.128.0.0 | (1/2 A) 128 B | |
4 194 304 | 4 194 302 | 255.192.0.0 | (1/4 A) 64 B | |
2 097 152 | 2 097 150 | 255.224.0.0 | (1/8 A) 32 B | |
1 048 576 | 1 048 574 | 255.240.0.0 | 16 B | |
524 288 | 524 286 | 255.248.0.0 | 8 B | |
262 144 | 262 142 | 255.252.0.0 | 4 B | |
131 072 | 13 107 | 255.254.0.0 | 2 B | |
65 536 | 65 534 | 255.255.0.0 | 1 B (256 C) | |
32 768 | 32 766 | 255.255.128.0 | (1/2 B) 128 C | |
16 384 | 16 382 | 255.255.192.0 | (1/4 B) 64 C | |
8 192 | 255.255.224.0 | (1/8 B) 32 C | ||
4 096 | 4 094 | 255.255.240.0 | 16 C | |
2 048 | 2 046 | 255.255.248.0 | 8 C | |
1 024 | 1 022 | 255.255.252.0 | 4 C | |
255.255.254.0 | 2 C | |||
255.255.255.0 | 1 C | |||
255.255.255.128 | 1/2 C | |||
255.255.255.192 | 1/4 C | |||
255.255.255.224 | 1/8 C | |||
255.255.255.240 | 1/16 C | |||
255.255.255.248 | 1/32 C | |||
255.255.255.252 | 1/64 C | |||
255.255.255.254 | 1/128 C | |||
255.255.255.255 | 1/256 C |
, , , ( ), , , 32 .
, , , (), . (RIP-2, IS-IS, OSPF) .